Drive mechanism for interproximal flossing device

ABSTRACT

An interproximal flossing device including a link member that isolates lateral from vertical rotational movement to transfer only translatory arcuate movement. This is done by the combination of a hinge and pivot structure. A tip attachment structure is also included for secure placement of the tip on the link member, and allows easy removal and replacement. A tip member removal structure is also included to allow for easy removal of the tip member from the link member.

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] The present application is a divisional application of U.S.patent application Ser. No. 09/636,488, filed on Aug. 10, 2000.

FIELD OF THE INVENTION

[0002] This invention relates to interproximal flossing devices, andmore particularly to the drive mechanisms for interproximal flossingdevices and the tip attachment structure associated therewith.

BACKGROUND OF THE INVENTION

[0003] Available interproximal flossers employ a variety of tipmovements to effect cleaning interproximal spaces formed between teeth.The tip movements typically include orbital, rotational, or linearmovement. Rotational movement is typically created by a direct linkagebetween the tip and the drive shaft of a motor mounted in the handle. Asthe drive shaft rotates, the linkage and tip also rotate accordingly.Typically the rotation occurs in one direction, but can also be rotaryoscillation. Rotation also occurs where the tip does not rotate aboutits longitudinal axis, but instead rotates about an axis offset from butgenerally parallel to the longitudinal axis of the tip. This Orbital tipmovement is often created by using an off-center weight attached to thedrive shaft of an electric motor mounted in the handle, which causes theentire device to move in an orbital manner in response to the off-centerrotation of the weight. Orbital movement can be considered a subset ofrotational movement because the tip rotates by moving along the orbitalpath.

[0004] Linear movement typically requires a linkage that converts therotational movement of the motor drive shaft into linear oscillatingmovement at the tip. Often times this structure for convertingrotational to linear movement requires an offset cam surface mounted onthe shaft of the motor with an end of the linkage attached thereto tofollow the eccentric as it rotates. The end of the shaft is generallyloosely engaged with the offset cam surface so that the shaft only movesin a direction to create linear motion at the tip end. In the linkageused to convert rotational movement to linear movement, there can beinefficiencies due to linkage connections (such as being looselyengaged), and difficulty in quietly connecting the linkage to the motorto avoid the creation of annoying sounds, due to loose connections, whenthe motor operates.

[0005] In addition, the tip connection structure typically used ininterproximal flossing devices utilizes simple friction to attach thetip to the active end of the drive train. This type of connection is notsecure, and can wear out and be less effective as the device is used.

[0006] It is with the above limitations of the presently availableinterproximal flossers that the invention described and claimed hereinwas developed.

SUMMARY OF THE INVENTION

[0007] The instant invention relates to a interproximal flossing device,and more particularly to the drive mechanism used in the device tocreate linear movement of the flossing tip. The interproximal flossingdevice of the present invention includes a link member that isolateslateral from vertical rotational movement to transfer only translatoryarcuate movement. This is done by the combination of a hinge and pivotstructure. A tip attachment structure is also included for secureplacement of the tip on the link member, and allows easy removal andreplacement. A tip member removal structure is also included to allowfor easy removal of the tip member from the link member.

[0008] In one aspect of the invention, it includes a drive mechanism foran interproximal flosser having an electric motor with a rotating driveshaft, the drive mechanism comprising a link member having a firstportion and a second portion, the first portion having a first end forattachment to the drive shaft in an off-center manner, and a secondportion having a second end for receiving a tip member; alaterally-extending pivot axis formed on the link member; and aresiliently flexible hinge portion having a vertical bending axis formedon the link member. When the drive shaft rotates, the first end of thelink member is rotated off-center from the drive shaft, creatingvertical, lateral, and a combination of vertical and lateral movement,and the hinge isolating the non-vertical movement from the tip memberwhile transmitting to the tip member vertical movement through thepivot, so that the tip member moves through a vertical arc.

[0009] In further detail, the hinge resiliently bends about a verticalaxis to isolate the lateral movement from the tip member.

[0010] In additional detail, the hinge resiliently twists about itsaxial axis to isolate the non-vertical movement from the tip membermotion.

[0011] In additional detail, the hinge resiliently bends about avertical axis to isolate the lateral movement from the tip member, andthe hinge resiliently axially twists about its axial axis to isolate thenon-vertical movement from the tip member motion.

[0012] In further detail, the drive mechanism defined above furtherincludes a drive member for attachment to the drive shaft, the drivemember defining a recess positioned offset to the drive shaft; the firstend of the link member is a ball; and the recess forms a socket forsnugly rotatingly and pivotingly receiving the ball.

[0013] In another aspect of the invention, the drive mechanism includesa link member having a first portion and a second portion, the firstportion having a first end, and a second portion having a second end forreceiving a tip member; a means for attaching the first end of the linkmember to the drive shaft in an off-center manner; a laterally-extendingpivot axis formed between the first and second portions; and aresiliently flexible hinge portion having a vertical bending axis formedon the link member. When the drive shaft rotates, the first end of thelink member is rotated off-center from the drive shaft, creatingvertical, lateral, and a combination of vertical and lateral movement,and the hinge isolating the non-vertical movement from the tip memberwhile transmitting to the tip member vertical movement through thepivot, so that the tip member moves through a vertical arc.

[0014] There are several different means for attaching, including a camand cam-follower structure, a ball and socket structure, a pair ofgears, a pair of opposing flexible hinges, each having a laterallyextending flexing axis formed on a sub-frame, a slider and slide channelhaving a substantially vertical motion, and a track cam surface forengagement with the first end of the link member.

[0015] In another aspect of the invention, an attachment structure forattaching a tip member to a link member of an automatic flosser includesa latch tab formed on the link member; and a latch recess formed on thetip member. When the tip member is positioned on the link member, thelatch tab engages the latch recess.

[0016] In further detail, the tip member has a cup-shaped portion withan open end and an interior wall; the latch recess includes a pair ofrecesses positioned on the inner wall; and the latch tabs includes apair of tabs formed on the link member to engage the corresponding latchrecesses when the tip member is positioned on the link member.

[0017] In further detail, a space is formed between the link member andthe inner wall of the cup-shaped portion to allow the cup shaped portionto be resiliently converted from a substantially circular form to asubstantially oval shape to disengage the latch tabs from the latchrecesses and remove the tip member from the link member.

[0018] In additional detail to the attachment structure as describedabove, the attachment structure includes a primary and secondary keyingstructure. The primary keying structure requires the tip member toattach to the link member in any of two orientations, with the twoorientations including the width of the blade extending vertically. Thesecondary keying structure requires the tip member to attach to the linkmember in one orientation, the one orientation including the blade ifcurving upwardly or downwardly.

[0019] In another aspect of the invention, a structure for removing atip member from a link member of an interproximal flosser includes aslot for receiving the tip member, the slot having side walls thatconverge along the length of the slot to engage and deform the tipmember as the tip member is moved along the slot.

[0020] The foregoing and other features, utilities and advantages of theinvention will be apparent from the following more particulardescription of a preferred embodiment of the invention as illustrated inthe accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0021]FIG. 1 is a top view of a flossing device incorporating the drivemechanism of the present invention, showing the primary internal workingparts in dash.

[0022]FIG. 2 is an enlarged section view taken along line 2-2 of FIG. 1,and shows the internal working parts, including the battery, D.C. motor,link member and tip member.

[0023]FIG. 3 shows an enlarged view of FIG. 2 with more detail.

[0024] FIGS. 3A-I are section views taken along respective lines of FIG.3.

[0025] FIGS. 4′, 4A′, 4B′, and 4C′ show the offset recess at variouspositions.

[0026]FIGS. 4, 4A, 4B, and 4C show top schematic views of the drivemechanism of the flosser of FIG. 1, with the eccentric drive member indifferent positions.

[0027]FIG. 5, 5A, 5B, and 5C show section views taken along respectivelines in FIGS. 4, 4A, 4B, and 4C showing the drive mechanism indifferent positions.

[0028]FIG. 6 shows another embodiment of the drive mechanism.

[0029]FIGS. 6A, B, C1, C2, C3, and D are section views taken alongrespective lines of FIG. 6.

[0030]FIG. 7 shows another embodiment of the drive mechanism.

[0031]FIG. 8 shows another embodiment of the drive mechanism.

[0032]FIG. 9 shows another embodiment of the drive mechanism.

[0033] FIGS. 1OA and B show another embodiment of the drive mechanism.

[0034]FIG. 11 shows another embodiment of the drive mechanism.

[0035]FIG. 12 shows another embodiment of the drive mechanism.

[0036]FIG. 13 shows another embodiment of the drive mechanism.

[0037]FIG. 14 shows an embodiment similar to that in FIG. 6, but with amore significant angle between the first and second portions of the linkmember.

[0038]FIG. 15 shows the tip member, including the tip cap, the flossingelement, and the recess groove.

[0039]FIGS. 16A and 16B show the first end of the link member forreceiving the tip member, and shows the key structure.

[0040] FIGS. 17A-D show the tip member without the secondary keystructure, and the connection structure for attachment to the linkmember.

[0041] FIGS. 17E-H show another embodiment of the tip member and theconnection structure for attachment to the link member.

[0042] FIGS. 18A-E show the link member, including the latch tabs.

[0043]FIGS. 19, 19A, 19A1 and 19B show a tip removal and storagestructure having a tip removal slot.

[0044]FIG. 20 shows the tip member attaching to the end of the linkmember.

[0045]FIGS. 21A, 21B and 21C show another embodiment of the tip removalslot.

[0046]FIG. 22 shows a detail of the second embodiment of the tip removalslot.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0047] Referring first to FIGS. 1 and 2, an interproximal flosser 30having the linear drive mechanism 32 of the present invention is shown.The interproximal flosser includes a housing 34 divided into twosections, a handle 36 in which the battery 38 and motor 40 reside, and atip portion 42. The tip portion 42 of the housing 34 encloses the lineardrive mechanism 32 as well as the on/off button 44. The tip portion 42generally extends at an angle downwardly from the handle 36 to provide adesired handle/tip portion orientation for use. The motor 40 is a DCmotor, known or available in the art, which includes a drive shaft 46which is driven in rotation by the motor. The motor 40 is powered by abattery, such as a AA or AAA battery, which can be rechargeable as isknown or available in the art. The motor shaft is attached to one end ofthe linear drive linkage 32 which extends inside the tip portion 42 tothe terminal end of the tip portion of the housing, and extendstherethrough to the outside of the tip portion 42. The exposed end ofthe drive linkage 32 receives a flossing member 48 through the use of atip connection structure 50 described in detail below.

[0048] The linear drive linkage 32 converts orbital or rotationalmovement of the motor drive shaft 40 to linear movement at the flossingmember 48. This is done by combining a horizontally-oriented pivot axis52 with a vertically-oriented hinge (axis of bending is vertical), onthe drive linkage 32, to effectively convert an orbital or rotationalmovement of the first end of the linkage into a linear movement at thesecond end 58 of the linkage. This linear movement is believed to be amore desirable flossing action than rotation (whether about the flossingmember's axis or an axis offset therefrom).

[0049] In greater detail, the linear drive linkage 32 includes a singleelongated link member 60 having a first end operably connected to thedrive shaft 46 of the motor 40, and a second end 58 extending from thetip portion 42 of the handle 36 for receiving the tip or flossing member48. The motor 40 is oriented in the handle 36 to generally rotate thedrive shaft 46 about the longitudinal axis of the housing. The lineardrive linkage 32 extends at an angle downwardly to follow the shape ofthe housing. See FIG. 2.

[0050] As shown in FIGS. 2 and 3, the first end of the link member 60 isattached to a drive member 62 (or offset connector), which is affixed tothe shaft 46 of the motor 40 and rotates with the shaft of the motor.The outer end of the drive member 62 defines an off-center recess 64,for instance a circular hole, for receiving the first end of the linkmember 60. This offset recess 64 causes the first end to rotate aroundthe shaft's 46 centerline (also characterized as moving in an orbitalmotion about the shaft's centerline) as the drive member 62 is rotatedby the shaft 46. This rotating motion of the recess and first end of thelink member 60 is generally concentric about the drive shaft 46.

[0051] The first end of the link member 60 can be of any reasonableshape for being received in the similarly-shaped off-center recess inthe drive member 62. Preferably, the drive member 62 has a circular orspherical off-center recess 64 formed therein for receipt of thepreferably substantially spherically-shaped first end of the link member60. A ball and socket type of structure is contemplated. It is importantthat the first end of the link member 60 be tightly held in the recess64 to minimize noise caused by the relative movement of the drive memberand the first end of the link member 60 when the drive member 62 isrotated. Further, the friction between the first end of the link member60 and the walls of the recess needs to be minimized to reduce wear andtear, and to reduce the energy consumption of the motor.

[0052] The link member 60 is divided into two portions, the firstportion 63 associated with the first end and the second portion 65associated with the second end 58. The two halves are generallydelineated by a pivot 66. See FIGS. 2 and 3. The pivot 66 on the linkmember extends horizontally (laterally at right angles with thecenterline of the flossing device) with respect to link member 60, andis restricted to allow pivotal movement in a vertical plane about ahorizontal axis only. The pivot 66 is formed by two cylindricalprotrusions, one extending from each side of the link member 60, eachbeing rotatably received in a yoke 68 formed in the housing. The yoke 68allows the protrusion to rotate therein about the horizontal pivot axis52. These cylindrical protrusions are restrained in the yokes 68 toallow only rotation about the pivot axis 52. The yokes can be formed bycylindrical recesses formed in the housing or other like structure.

[0053] A flexible hinge 70 is formed in the link member 60 adjacent tothe pivot 66 and in the first portion 63. The flexible hinge 70 has thefull dimension of the height of the link member 60 in a verticaldirection and is very thin relative to the height of the link member inthe side-to-side direction (FIG. 2). The flexible hinge 70 is ideally a“living hinge” (made out of the same material as the rest of the linkmember 60, or can be a separate resilient member attached into the linkmember) 60. The flexible hinge 70 acts to allow the first section 63 ofthe link member 60 to bend laterally and twist axially when the firstend of the link member 60 moves with the rotation of the off-centerrecess 64 in the drive member 62. The hinge 70 twists to absorb thelateral movement of the first end that is not purely horizontal. Thislateral movement and twisting motion is thus isolated by the hinge sothe second section 65 of the link member 60 moves only in a linearmanner up and down about the pivot axis 52 of the pivot 66. It isbelieved that the hinge can be approximately 0.037 inches in thickness,0.150 inches long, and 0.13 inches tall. The surrounding portion of thelink member 60, before and after the hinge, is 0.1 inches thick, and0.13 inches tall.

[0054] The hinge 70, which is flexible, preferably resiliently toautomatically be biased back to its original position, in theside-to-side direction (in its thin dimension), and can twist, incombination with the fixed pivot, isolates the vertical motion from thegenerally rotary motion of the first section 63 of the link member 60.This vertical oscillating motion is transmitted to the second section 65of the link member 60 to move the flossing tip 48 in a vertical, planar,reciprocating accurate motion.

[0055] When the first end of the link member 60 moves up and down as theoff-center recess 64 in the drive member 62 moves from top to bottomduring rotation, the hinge 70 bends laterally and twists axially, yetthe larger (vertical) dimension of the hinge 70 is substantially rigidand thus transfers vertical motion through the pivot point to cause thepivot 66 to rotate or pivot along its horizontal axis This in turncauses the second end 58 of the link member 60 to move through avertical arc with respect to FIG. 2 in a reciprocating, linear (ortranslatory) motion. The desired motion at the end of the tip member 48is vertical, up-and-down movement in a single plane through an arc. Thistranslatory motion is the desired motion for the tip 48 when cleaningthe interproximal spaces between teeth.

[0056] The second end 58 of the link member 60 is free to move in thetranslatory motion inside the housing 34 and outside the housing suchthat when a tip member 48 is attached to the second end 58 of the linkmember 60 the tip member also moves in a translatory motion. Theflexible hinge section 70 of the link member 60 acts as a living hingeto effectively absorb and isolate the side-to-side or lateral movementand twisting motion of the first end of the link member 60 and allowsonly the vertical up-and-down movement of the first end of the linkmember 60 to be transferred through the pivot 66 to the second end 58 ofthe link member 60 to cause the tip member 48 attached thereto to moveup and down in a translatory linear oscillating motion defining an arc.This isolates the vertical movement components from the lateral movementcomponents. The pivot restraint (yokes) 68 also isolates the lateralmovement components from the vertical movement components.

[0057] Typical cam and follower structures, because of the clearancerequired, generate significant noise when the motor operates atapproximately 9,000 rpm (the desired speed). To reduce this noise, theinstant invention employs a ball-shaped first end of the link member 60to be received in the off-center recess 64 (socket) of the drive member62. The ball or spherical shape of the first end of the link member 60can be more tightly toleranced with the off-center recess 64 in thedrive member 62 to minimize the clearances and thereby reduce the noiselevel during operation. A ball and socket structure is shown in FIGS. 2and 3.

[0058]FIGS. 4, 4A, 4B, 4C, 5, 5A, 5B, 5C schematically show the drivemechanism 32 of the present invention in four different positions toshow how the flossing member 48 and second end 58 of the link member 60move relative to the first end of the drive link member 60. FIGS. 4, 4A,4B, and 4C show top views of the drive mechanism in four consecutivepositions. FIGS. 5, 5A, 5B, and 5C are vertical section views to showthe link member 60 and flossing member 48 position corresponding toFIGS. 4, 4A, 4B, and 4C, respectively.

[0059]FIGS. 4 and 5 show the link member 60 with the drive member 62 inthe top position (the offset recess pointing directly upwardly at 12o'clock, as shown in FIG. 4′). This is the highest vertical offsetposition and the smallest lateral offset position the first end of thelink member 60 is subject to above the centerline, and thus is thelowest position of the second end 58 of the link member 60 and theflossing member 48. In this position the hinge 70 is transferring all ofthe vertical motion of the first end of the link member 60 to the secondend 58 of the link member 60 through the pivot 66. This position isrepresented by dashed line ww.

[0060]FIGS. 4A and 5A show the link member 60 with the drive member 62in the left-most position (the offset recess pointing generally at 9o'clock, as shown in FIG. 4A′). This is the smallest vertical offsetposition and the highest lateral offset position the first end of thelink member 60 is subject to relative to the centerline, and thus is theintermediate position of the Second end 58 of the link member 60 and theflossing member 48. In this position the hinge 70 is bending to absorbsubstantially all of the lateral motion of the first end of the linkmember 60, thus isolating the second end 58 of the link member 60therefrom. The pivot 66 is not activated, and the link member 60 is thusin an intermediate or neutral position. This position is represented bydashed line xx.

[0061]FIGS. 4B and 5B show the link member 60 with the drive member 62in the top position (the offset recess pointing directly downwardly at 6o'clock, as shown in FIG. 4B′). This is the relatively lowest verticaloffset position and smallest lateral offset position the first end ofthe link member 60 is subject to below the centerline, and thus is thehighest position of the second end 58 of the link member 60 and theflossing member 48. In this position the hinge 70 is transferring all ofthe vertical motion of the first end of the link member 60 to the secondend 58 of the link member 60 through the pivot 66. This position isrepresented by dashed line yy.

[0062]FIGS. 4C and 5C show the link member 60 with the drive member 62in the right-most position (the offset recess pointing generally at 3o'clock, as shown in FIG. 4C′). This is the smallest vertical offsetposition and the highest lateral offset position the first end of thelink member 60 is subject to relative to the centerline (equal to the 9o'clock position), and thus is the intermediate position of the secondend 58 of the link member 60 and the flossing member 48. In thisposition the hinge 70 is bending to absorb substantially all of thelateral motion of the first end of the link member 60, thus isolatingthe second end 58 of the link member 60 therefrom. The pivot 66 is notactivated, and the link member 60 is thus in an intermediate or neutralposition. This position is represented by dashed line zz.

[0063] The stroke of the flossing member 48 is thus represented by theplane formed between dashed line ww and yy. Ideally, the motion of thetip of the flossing member 48 is approximately between 0.050 inches to0.070 inches, at an angle of between 5 and 30 degrees (no angle requiredif entire flossing tip translates, as described below), and at a speedof 9,000 cycles per second. The flossing member 48 is moved through thisstroke efficiently and with reduced noise.

[0064] The structure described above with respect to FIGS. 1, 2, 3,4-4C, and 5-5C is a preferred embodiment for the present invention. Itcombines the desired noise level with the positioning of the pivot 66and supporting yoke 68 to help the device have the desired size for easeof manipulation during use. If the pivot 66 is too close to the flossingmember 48, the device would be more difficult to insert into a user'smouth. If the pivot 66 is too far away from the flossing member 48, thedevice would be longer than is necessary, and the link member 60 wouldneed to be made larger to handle the moment loads. Nonetheless, avariety of different embodiments are possible for converting rotationalmovement to the preferred translatory movement. The similarity betweenall embodiments is that the link member 60 includes a hinge portion 70and a fixed pivot 66 to isolate the vertical motion of the link member.Most of the differences described below address the engagement of thedrive shaft 46 of the motor 40 to the first end 56 of the link member60. Some of these other means for quietly and efficiently convertingrotation into linear motion are described below.

[0065]FIG. 6 shows an embodiment where a flexible cable 80 is used toremotely position the connection of the link member 82 from the motor40. This could be helpful if this connection was required to be offsetfrom the motor for some reason. The cable 80 is attached at one end tothe drive shaft 46, and at the other to an eccentric cam 84. A rotationbearing 86 supports the distal end of the cable and allows it to rotatewith the drive shaft 46. The eccentric cam 84 can be used to drive asmall link member 82 which includes a cam follower 88. The tip member(not shown) attaches to the end 90 of the small link member 82. Thesmall link member has a pivot 92 to allow the link member to pivot abouta fixed horizontal axis. The cam follower 88 is designed to follow therotation of the eccentric in the vertical, up-and-down direction. Thesmall link member 82 forms a living hinge 94, similar to the previousembodiment, to absorb (bend and twist) to isolate the lateral motionfrom the motion of the cam follower 88. This allows just the verticalmotion to pass through the pivot 92 and cause the flossing member topivot up and down through the desired planar arc, as shown.

[0066]FIGS. 6A shows a section of the small link member through thepivot protrusions and support yokes 96. FIG. 6B shows a section throughthe hinge section of the small link member. FIG. 6C1-6C3 show variouspositions of the cam follower 88 relative to the rotating drive shaftextension 80. FIG. 6C1 shows the cam follower 88 in its highestposition. FIG. 6C2 shows the cam follower 88 at its largest lateraldeviation, and FIG. 6C3 shows the cam follower 88 in its lowestposition. FIG. 6D shows a section of the remote end of the drive shaftin the rotation bearing 86.

[0067]FIG. 7 shows a structure utilizing bevel gears 110. The small linkmember 112 and cam follower 114, as well as motor 40 are identical tothat described above with respect to FIG. 6. The structure of FIG. 7would allow for angular relation of the input to output, but wouldminimize the parasitic drag on the system existing in the structure ofFIG. 6. This would have fewer complications than use of a universaljoint, which could be used to replace the bevel gears 110 and would alsowork in this instance. The gear shafts and attachment ends couldpotentially be molded into one piece for each shaft. The eccentric 116could be molded as a part of one of the shafts also. This design wouldrequire one or two rotational bearing features 118 for each shaft whichcould cause some parasitic drag. However, if the shaft with one of thegears of the eccentric was used to replace the existing eccentric 116and the other shaft with its gears, and a mounting feature to the motorwas used to replace the existing long rocker arm, there would be anequivalent number of parts. There may be gear noise as well as heatbuildup at the gear faces, however, a potential advantage is that sincethis is a geared system the output speed (tip movement frequency) can bevaried from the motor rotational speed. This may be beneficial in termsof cleaning effectiveness, motor selection, flexibility, and powerrequirements.

[0068] The cam-followers 88 and 116 of the structures of FIGS. 6 and 7can be designed to only follow the eccentrics in the vertical up anddown motion, not in the lateral direction. This would mean the linkmember would not have to include a flexible hinge portion to isolate thevertical motion.

[0069]FIG. 8 shows a DC motor 40 with the drive shaft 46 mounteddirectly to the eccentric 120. The small link member 122 and camfollower 124, as well as motor 40, are identical to that described abovewith respect to FIGS. 6 and 7. The small pivot arm 122 pivots about thepivot point 126, similar to structures of FIGS. 6 and 7. Again, becauseof the flexible hinge in the link member, the flossing member (notshown) follows only the vertical movement of the eccentric 120. In thisembodiment, the motor is positioned very close to the flossing member.

[0070]FIG. 9 shows a structure similar to that of FIG. 8, except the tip150 is attached directly to the off-center eccentric 152 mounted on themotor drive shaft 46, as opposed to a cam follower. The tip 150 combinesboth the tip member and the small pivot arm, and includes the pivotpoint 154 and the flexible hinge 156. The examples shown in FIGS. 8 and9 rely on a DC motor being sufficiently small enough to fit in the tipportion of the housing. This option, depending on available space andmotor capability, has a potential for the fewest number of drivemechanism components. With the redesigned combination tip 150, even theexisting prototype mechanism could eliminate the small pivot arm. Thebiggest difference between the function of the redesigned tip designs isthat the use of this tip with the existing long rocker arm design yields“single plane” oscillation, where use of the above-listed simplifieddesign yields orbital motion unless special steps are taken, likeconstructing the tip beam that engages the eccentric so it flexes easilyin the horizontal (lateral) direction but is very stiff in the verticaldirection. Or, as described above with the various embodiments, theengagement between the tip 150 and the eccentric 152 could work tofollow the cam (eccentric) in only the vertical movement and not theside-to-side or lateral movement.

[0071] Another option to obtain more pure “single plane” oscillationwould be to create a “living flex” cantilever beam structure 160utilizing a subframe 162 in the housing. This could take the eccentricrotational motion from the motor and turn it into “single plane”translatory oscillation. See FIGS. 10A and B. FIG. 10A shows a framestructure 162 having a living hinge 164 at the top and bottom areas toisolate the orbital movement of the eccentric 166 to cause simply linearmotion in the vertical direction at the tip of the flossing member 168.The subframe is attached to an off-set drive shaft 168 for simplicity inexplanation. The frame structure 164 is rigid in the lateral and othernon-vertical directions, thus isolating those motions from the flossingmember 168. The combination tip 168 would be similar to that shown inFIG. 9. FIG. 10B shows the frame 164 flexed upwardly, thus pushing theflossing member downwardly. The frame 164 would flex downwardly the sameamount to generate the stroke as shown. In FIG. 10A, the frame is in theun-flexed position. This structure is basically a pair of opposingflexible hinges, each having a laterally extending flexing axis formedon a sub-frame. Another option related to this “living flex” conceptwould be to do away with the tip pivot and simply have a tip attached tothe projection of the living flex element. This would enhance the“sealability” of the unit since the projection of the living flexelement could be sealed to the main structure. However, depending on thespace available, it may be necessary to position the motor and flexmechanism a significant (over 1.5 inches) distance away from the actualtip.

[0072] Another variation on this structure would be to replace theliving flex portion of the mechanism with a slide channel 200 in thesubframe of the housing, as shown in FIG. 11. This structure may requireless force to move the tip holder since it is not flexing a member tocreate movement, but rather sliding a preferably low-frictionfree-flowing element. However, depending on the distance to the tip, abinding condition could exist in the slide channel contact area, whichcould degrade performance. In FIG. 11, the off-center cam 202 isattached to a slider 204, which is positioned in the slide channel 200,with the entire slider 204 moving up and down. Since the flossingelement 206 is attached directly to the slider 204, the entire flossingtip moves up and down in pure translation, without any pivoting motion.See the outer dashed lines in FIG. 11 to show the approximate upper andlower positions. The angle of the flossing member 206 relative to themotor is easily adjustable by simply adjusting the angle at which theflossing member attaches to the slide member 204. This structure isbasically a slider 204 and slide channel 200, the slide channel allowingonly a substantially vertical movement of said slider.

[0073] Another embodiment using pure rotary input motion with the motor40 somewhat remote from the tip 210 would include a track cam 212attached to the motor shaft 214 with the second end of the link member216 engaging the track cam 212. See FIG. 12. The tip member 210 ispivotally mounted to the housing such that when the tip member 210 movesin the cam track 212 the external portion of the tip member 210 moves ina vertical arc, up and down. The first half of the link member 216 canbe flexible to isolate the side-to-side movement as the first end isactuated by the track, and thus only pass the vertical movement throughthe pivot point. This structure reduces the drive system down to themotor and one fairly straightforward member (the rotating track camelement 212). The replaceable tip 210 is driven directly from the trackcam 212. Since the motor bearings and bushings support the end of thetrack cam shaft, if the shaft needs to be long because of spaceconstraints, then only one additional bearing surface should be requiredto constrain the shaft. However, if the space constraints allow themotor to be positioned close to the tip actuation point, then the motorbearings and bushings would be all that is required to support theshaft, because the shaft becomes very short. Also, this pure rotationshould be much more in balance than the eccentric cam scheme of theprior art. With only the lightweight plastic flossing tip oscillating,the handle vibration should be reduced to a minimum. A seal could bepositioned on this track cam shaft 212 as is known in the art, and theangled end portion of the device could be the color-coded,interchangeable nosepiece for different family members to use ascontemplated.

[0074]FIG. 13 shows an alternative structure for attacking the linkmember 60 to the drive shaft 46. The drive shaft has an offset portionwhich is notably engaged in the first end 56 of the link member 60. Theoffset portion acts like the combination of the drive member 62 andrecess 64 of the structure in the embodiment of FIGS. 1, 2 and 3.

[0075]FIG. 14 shows an alternative embodiment of the drive mechanism,similar to that of FIG. 7, with a more significant angle between thefirst and second portions of the link member 112′. Also, the camfollower 114′ follows a camming device 116′, which is attached to adrive member 115, which is in turn attached to the drive shaft 46. Thisstructure allows a direct attachment of the link member to the motor.The offset angle formed between the portions of the link member,delineated by the pivot, allow for different relative positions of theflossing member with respect to the motor.

[0076] The linear drive linkage of the present invention efficientlyconverts pure rotary motion to oscillating translatory motion (pivotalup and down movement through a vertical plane) for effective flossingaction in the interproximal gaps between one's teeth. The structuresdescribed herein minimize or eliminate any side to side movement of thetip member by isolating the up and down movement from the lateralmovements through the drive structure between the rocker arm and themotor drive shaft. Preferably, a combination horizontal pivot andvertically oriented flexible section of the rocker arm are used incombination to isolate the up and down vertical motion and eliminate theside to side or lateral motion.

[0077] The second end of the link member is designed to receive the tipmember. Preferably, the tip member is both securely attached to thesecond end of the link member, yet can be easily released therefrom forreplacement. FIG. 15 shows the structure of the tip member. The tipmember 250 generally includes a tip cap 252 from which extends theflossing element 254. The flossing element 254 and tip cap 252 are madeof plastic. The flossing element 254 extends from the center of the endof the tip cap 252 and can be straight, curved or a combination of both.The flossing element 254 is sized to be received in the interproximalspaces. The tip cap 252 has a cup-like shape forming a cavity with aclosed end 256 from which the flossing element extends and an open end258 which receives the second end of the link member. Adjacent the openend 258 , an annular groove 260 is formed on the interior wall 262 ofthe tip cap 252.

[0078] Adjacent the closed end 256 of the tip cap a keying feature 264is formed on the lower side walls thereof. See FIG. 15. The keyingfeature 264 can be an angled plane or the like as described in greaterdetail below. The tip cap 252 is typically generally cylindrical, butcan be deformed to an oval shape as described below. Also, the annulargroove 260 does not have to extend around the circumference of theinterior of the tip cap at a location adjacent the open end, but insteadcan be diametrically opposed recesses, for instance at the top andbottom as shown in FIG. 15. The purpose of the latching recess will bedescribed in greater detail below.

[0079]FIGS. 17A, B, C and D also show the tip member. Here there is nosecondary keying feature, just a rectangular aperture 266 allowing thetip to be mounted one of two ways on the end of the link member. This isappropriate where the flossing member is straight and thus there is noup or down orientation. The tip material is preferably Dupont Zytel□101L, or the like, such as NC010 (nylon 66).

[0080]FIGS. 16A and 16B show a preferred structure of the second end 270of the link member 272. Link member 272 is similar to link member 60described above, and can be used in any embodiment described herein. Thesecond end of the link member is sized to fit within the tip cap of FIG.15, and includes diametrically opposed latch tabs 274 that snap into thelatching recess when the second end of the link member is inserted intothe tip cap 252. A keying structure 276 is incorporated into the secondend to mate with the keying structure 264 of the tip. The key structurecan have a primary key and a secondary key. The primary key is neededregardless of whether the tip is curved or straight, and insures thatthe tip is mounted so that it vibrates along the skinny axis of theblade so it fits appropriately between the user's teeth. The primary keysimply helps insure that the end of the link member is rectangular andonly accepts the tip in two corresponding orientations.

[0081] The secondary key is necessary where the tip is curved and thushas a proper up and down orientation. A preferred keying feature 276 isdefined near the second end 270 of the link member 272 to mate with thesecondary keying feature 264 inside the tip cap 252. This secondarykeying feature allows the tip cap 252 to be positioned in only oneorientation on the second end of the link member in the event theflossing element is curved and requires a particular orientation forproper use. The secondary keying feature is not required unless theparticular orientation of the tip cap 252, when mounted on the secondend of the link member, is desired. Other types of secondary keyingfeatures can be used, including other geometrical shapes, notches andgrooves, or the like, to allow an engagement of the keying features forinsertion of the second end of the link member into the tip cap. Thepreferred secondary keying feature described herein is preferred becauseof its ease of manufacture and simplicity.

[0082] A sealing surface 280 is defined on the second end 270 of thelink member 272 spaced away from the latch tabs 274 and on the side ofthe latch tabs away from the free end of the link member. The rim of thetip cap 252 engages the sealing surface 280 (which can be an annularboss formed around the link member).

[0083] FIGS. 18A-E shows an alternative embodiment of the second end ofthe link member not requiring a keying feature. The link member issimilar to that shown in FIGS. 1, 2 and 3.

[0084]FIGS. 17E, F, G and H show an embodiment of the tip cap 252 andflossing element 254. The external surface of the tip cap 252 adjacentthe rim defines opposed notches. The primary and secondary keyingstructures are combined in this structure by having a pie-shaped openingin the tip cap to receive a correspondingly-shaped second end of thelink member.

[0085] In operation the enclosed latching recess 260 in the tip cap 252engages the latching tabs 272 on the mechanism (the second end of thelink member) to hold the tip in place. The keying feature prevents thetip from being installed in the improper orientation if that feature isdesired. The tip is disengaged from the second end of the link member bycompressing the sides of the tip cap 252 to deform it into essentiallyan elliptical shape. This would create a major axis of an ellipse whichwould be larger than the distance across the latching tabs 272 on thesecond end of the link member. The tip could then be easily removedbecause the latch tabs disengage from the latch grooves when thesidewalls are squeezed.

[0086] A tip-holding cartridge could provide the compression means forinsertion or removal without the user having to directly contact thetip. There is a gap formed on either side of the second end of the linkmember when inserted in the tip cap to allow the tip cap to be squeezedto form an elliptical shape. The tip cap can deformed to an ovalized ornon-circular shape to release the latch tabs 272 from the latch recesses260.

[0087] This detent-style tip connection allows for secure placement ofthe tip member on the second end of the link member yet also allows forconvenient removal of the tip member from the second end of the linkmember. When the tip member is positioned on the second end of the linkmember, an audible “click” is heard when the tip member is correctlyseated thereon. This is a positive feature for assuring the user thatthe tip member is firmly attached to the device.

[0088] The latch tabs 274 can have at least a sloped front surface 290(see FIG. 18E) to allow for a sliding engagement of the tip cap 252 overthe second end of the link member so that the tip cap 252 is graduallyincreased in size to allow the latch tabs 274 to seat in the latchingrecess 260. The tip cap 252 is sufficiently resilient to rebound to itscircular shape to cause the latch tabs 274 to be received in the latchrecesses 260 and thus hold the tip on the second end of the link member.

[0089] The tip can be removed from the second end of the link member bysqueezing the sides of the tip that are offset approximately 90 degreesfrom the engagement of the latch members 274 with the latch recesses 260in the tip cap 252. Compressing the tip cap 252 at this location causesthe tip cap to form an elliptical or oval shape, disengaging the latchtabs from the latch recesses 260 and allows the tip cap 252 to beremoved from the device. This can be done by hand, with a tool, such aspliers, or by the tip removal device shown in FIGS. 19, 21, and 22.

[0090]FIG. 19 shows a flosser tip cartridge 300 including severalreplacement flosser tip members 302 positioned circumferentially aroundthe outer rim of the top cap, and a specially formed slot 304 formedacross the center of the top cap. Once the flosser tip 250 is attachedto the second end of the link member, as is shown in FIG. 20, theflosser tip is releasably attached thereto. To remove the flosser tipfrom the second end of the link member, the flosser tip 250 is insertedinto the slot 304 at the first end 306, as shown in arrows of FIG. 19B,and then moved along the slot 304 to compress the opposing sides of thetip cap 252 and release the latch tabs 274 to allow the tip 250 to fallinto the reservoir 300 for easy collection and disposal.

[0091] The first end 306 of the slot 304 has a substantially circularshape to allow the insertion of the tip 250 therethrough. The upperedges 308 of the slot 304 slope outwardly at the first end 306 andgradually transition to a vertical orientation about half way betweenthe first end 306 and the second end 310 of the slot. The seal collar280 (FIG. 15) formed around the second end of the link member rests onthe top edge of the slot 304 and as the tip 250 is moved along the slot,the sides are compressed by the side walls of the slot 304 to cause thetip cap 252 to be deformed into an elliptical shape to allow the latchtabs 274 to be released from the latch recesses 260. See FIG. 19A1 foranother representation of the slot shown in FIGS. 19A and B. The sidesof the slot 304 preferably engage the opposing notches on the sides ofthe tip cap 252. At the second end 310 of the slot 304, when theflossing device is pulled upwardly from the slot 304, the tip 250 isheld in the slot 304 such that it is removed from the second end of thelink member.

[0092]FIGS. 21A, B and C show another embodiment of this tip removaldevice where the slot 304A is broken into at least two sections: onesection 312 being similar to that shown in FIGS. 19A and B where the tipis deformed into an elliptical shape such that the latch tabs 274 arereleased from the latch recesses 260 in the tip, and a second section314 where the tip 250 is forcibly removed and ejected from the secondend of the link member without having to remove the second end of thelink member from the slot 304. This structure entirely removes theflosser tip 250 from the second end of the link member and ejects itinto the receptacle cavity. The first end 306 of this slot 304A in FIG.21A is for receiving the flosser tip 250. As the flosser tip 250 ismoved along the slot 304A, a first downwardly sloped surface 316 (FIG.21B) on either side of the slot 304A engages the sides of the flossertip 250 to compress the flosser tip 250 into an elliptical shape andrelease the latch mechanisms to allow the flosser tip to be slid towardsthe end of the second end of the link member. The sidewalls preferablyengage the opposing notches on the tip cap 252, and push the tip capalong the second end of the link member by moving down the ramp as thecap is moved along the first section of the slot.

[0093] At the second section 314 of the slot 304A, a second downwardlysloping ramp 318 (FIG. 21B), offset upwardly from the first downwardlysloping ramp, is formed on either side of the slot 304A and engages thetop side of the rim of the tip cap 252 to further force the flosser tip250 all the way off the second end of the link member as the device ismoved to the second end of the slot. See FIG. 21C.

[0094]FIG. 22 shows an enlarged view of the slot 304A structure incross-section. Again, the slot ramp 316 acts to compress the tip cap 252to cause it to form an elliptical shape to disengage the latch tabs 274and push the flosser tip 250 partially from the second end of the linkmember. The final ejection ramp 318 in the second section 314 of theslot engages the rim of the flosser tip to finally push the entireflosser tip off the second end of the link member as the device is movedto the second end 310 of the slot 304A. Using the slot to compress thetip 250 and release the latch tabs 274, additional features were addedto eject the tip from the end of the device and are summarized here. Thetip 250 is inserted into the release slot 304A. As the tip 250 is slidalong the slot 304A and compressed to release the latch tabs 274, it isalso guided down the slot ramp 316. This pulls the tip 250 down and offthe attachment end of the device. As the tip 250 clears the end of theslot ramp 316, the very end (the rim) of the tip cap 252 contacts thefinal ejection ramp 318 and is pushed clear of the tip attachment end ofthe device (see FIG. 21C also).

[0095] The automatic removal of the flosser tip from the end of thedevice is a convenience to allow the user to easily replace the tips bysliding the second end of the link member along the slot, removing thetip member and easily replacing the tip by simply inserting it into anew flosser tip stored adjacent to the slot.

[0096] While the invention has been particularly shown and describedwith reference to a preferred embodiment thereof, it will be understoodby those skilled in the art that various other changes in the form anddetails may be made without departing from the spirit and scope of theinvention.

We claim:
 1. A structure for removing a tip member from a link member ofan interproximal flosser, said structure comprising: a slot forreceiving the tip member, said slot having side walls that convergealong the length of the slot to engage and deform the tip member as thetip member is moved along the slot.
 2. The structure for removing a tipmember in claim 1, said structure further comprising: a ramp surfacethat contacts said tip member as the tip member is moved horizontallyalong said slot thereby causing the tip member to eject vertically fromsaid link member.
 3. The structure for removing a tip member in claim 1,said structure further comprising: a lower slot surface that engages akey feature in said tip member thereby restricting the orientation ofsaid tip member within said slot to ensure said tip cap will properlydeform when slid along said slot.